Asymmetric yoke

ABSTRACT

An evacuation assembly may comprise an evacuation slide and a first yoke coupled to the evacuation slide. The first yoke may comprise a first strap and a second strap. The first strap may be longer than the second strap. The evacuation assembly may optionally include a second yoke coupled to the evacuation slide. A first strap of the second yoke may be longer than a second strap of the second yoke.

FIELD

The present disclosure relates to aircraft evacuation assemblies, andmore specifically to restraint devices for evacuation slides and methodsof making an evacuation assembly.

BACKGROUND

An evacuation slide assembly may include an inflatable slide that helpspassengers disembark from an aircraft in the event of an emergency orother evacuation event. The slides may deploy from a door sill or a sideof the aircraft fuselage. A common problem associated with inflatableevacuation slides, however, is that when such slides are deployed inhigh lateral wind conditions, the wind may cause the slide to “kite”such that the toe end of the slide does not touch the ground, renderingthe slide less usable. If the slide lifts off the ground to a pointabove the airplane's door sill height after full extension, the slidemay block the aircraft exit and prevent safe evacuation of passengersand crew. Further, for slides located near a forward end of an aircraftengine, any kiting is disfavored, as it could lead to contact with theengine.

SUMMARY

Disclosed herein, according to various embodiments, is an evacuationassembly. An evacuation assembly may comprise an evacuation slide; and adeployment assembly coupled to the evacuation slide and configured suchthat during a deployment of the evacuation slide a forward portion of atoe end of the evacuation slide contacts an exit surface prior to an aftportion of the toe end of the evacuation slide.

In various embodiments, the deployment assembly may comprise a firstyoke comprising a first strap and a second strap, wherein the firststrap is longer than the second strap. The first strap may be coupled toa forward portion of the evacuation slide and the second strap may becoupled to an aft portion of the evacuation slide. A ratio of a lengthof the first strap to a length of the second strap may be from 6:5 to4:1. The first strap may be between 6 inches and 9 feet longer than thesecond strap.

In various embodiments, the deployment assembly may further comprise asecond yoke, wherein a first strap of the second yoke is longer than asecond strap of the second yoke. The second yoke may be located closerto the toe end of the evacuation slide than the first yoke. A firstreleasable restraint may be coupled between the first yoke and theevacuation slide; and a second releasable restraint may be coupledbetween the second yoke and the evacuation slide, wherein the firstreleasable restraint is configured to separate prior to the secondreleasable restraint during the deployment of the evacuation slide. Adifference in a length of the first strap of the first yoke and a lengthof the second strap of the first yoke may be greater than a differencein a length of the first strap of the second yoke and a length of thesecond strap of the second yoke.

In various embodiments, the deployment assembly may further comprise athird yoke coupled to the evacuation slid, wherein a first strap of thethird yoke and a second strap of the third yoke may be approximatelyequal in length. The third yoke may be positioned closer to a head endof the evacuation slide than the first yoke and the second yoke.

In various embodiments a yoke for an evacuation system is disclosed. Ayoke for an evacuation system may comprise a first strap and a secondstrap coupled to the first strap, wherein the first strap is longer thanthe second strap.

In various embodiments, a ratio of a length of the first strap to alength of the second strap may be from 6:5 to 4:1. The first strap maybe from 6 inches to 9 feet longer than the second strap. The first strapand second strap may be sewn together.

In various embodiments, a method of making an evacuation assembly isdisclosed. A method of making an evacuation assembly may comprisecoupling a first yoke to an evacuation slide, the first yoke comprising,a first strap and a second strap, wherein the first strap is longer thanthe second strap.

In various embodiments, the method may further comprise coupling thefirst strap to a forward edge of the evacuation slide, and coupling thesecond strap to an aft edge of the evacuation slide. The method mayfurther comprise coupling a second yoke to the evacuation slide, whereina first strap of the second yoke is longer than a second strap of thesecond yoke. A difference in a length of the first strap of the firstyoke and a length of the second strap of the first yoke may be greaterthan a difference in a length of the first strap of the second yoke anda length of the second strap of the second yoke. The method may furthercomprise coupling the second yoke closer to a toe end of the evacuationslide than the first yoke.

The forgoing features and elements may be combined in variouscombinations without exclusivity, unless expressly indicated hereinotherwise. These features and elements as well as the operation of thedisclosed embodiments will become more apparent in light of thefollowing description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of an evacuation slide in adeployed position, in accordance with various embodiments;

FIG. 2 illustrates a perspective view of an evacuation slide in a stowedposition, in accordance with various embodiments;

FIGS. 3A, 3B, and 3C illustrate a releasable restraint retaining anevacuation slide in a folded position, in accordance with variousembodiments;

FIGS. 4A, 4B, 4C, and 4D illustrate deployment of an evacuation slide,in accordance with various embodiments;

FIG. 5 illustrates an underside surface of an evacuation slide in adeployed position, in accordance with various embodiments;

FIG. 6 illustrates an asymmetric yoke, in accordance with variousembodiments; and

FIG. 7 illustrates of a method of making an evacuation assembly, inaccordance with various embodiments.

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the drawing figures, wherein like numeralsdenote like elements.

DETAILED DESCRIPTION

The detailed description of exemplary embodiments herein makes referenceto the accompanying drawings, which show exemplary embodiments by way ofillustration. While these exemplary embodiments are described insufficient detail to enable those skilled in the art to practice theexemplary embodiments of the disclosures, it should be understood thatother embodiments may be realized and that logical changes andadaptations in design and construction may be made in accordance withthis disclosure and the teachings herein. Thus, the detailed descriptionherein is presented for purposes of illustration only and notlimitation. The steps recited in any of the method or processdescriptions may be executed in any order and are not necessarilylimited to the order presented

Furthermore, any reference to singular includes plural embodiments, andany reference to more than one component or step may include a singularembodiment or step. Also, any reference to attached, fixed, connected orthe like may include permanent, removable, temporary, partial, fulland/or any other possible attachment option. Additionally, any referenceto without contact (or similar phrases) may also include reduced contactor minimal contact. Surface cross hatching lines may be used throughoutthe figures to denote different parts but not necessarily to denote thesame or different materials.

Throughout the present disclosure, like reference numbers denote likeelements. Accordingly, elements with like element numbering may be shownin the figures, but may not be necessarily be repeated herein for thesake of clarity.

As used herein, “aft” refers to the direction associated with the tail(i.e., the back end) of an aircraft, or generally, to the direction ofexhaust of the gas turbine. As used herein, “forward” refers to thedirection associated with the nose (i.e., the front end) of an aircraft,or generally, to the direction of flight or motion.

Evacuation slides according to the present disclosure may extend from anaircraft structure, such as, for example, a fuselage or a wing, to anexit surface in a fully deployed position. During deployment, adeployment assembly coupled to the evacuation slide may aid incontrolling the inflation and deployment of the slide. The deploymentassembly according to the present disclosure, may allow forward portionsof the slide to open and/or inflate and/or unfold at a faster rate thanaft portions of the slide to prevent kiting of the slide and/or cause aforward portion of the toe end of the slide to contact the exit surfaceprior to an aft portion of the toe end of slide. The deploymentassembly, according to the present disclosure, may comprise one or moreasymmetric yokes.

With reference to FIG. 1, an exemplary aircraft 100 is shown, inaccordance with various embodiments. Aircraft 100 may comprise afuselage 102 with wing 104 fixed to fuselage 102. Engine 108 may becoupled to an underside of wing 104. Emergency exit door 106 may belocated on fuselage 102, forward wing 104 and engine 108. An evacuationslide 110 may be deployed from emergency exit door 106. Evacuation slide110 may comprise a head end 112 and a toe end 114 opposite head end 112.Head end 112 may be coupled to aircraft structure 100. Evacuation slide110 may comprise a sliding surface 116 (also referred to as a topsurface) and a rear surface 118 (also known as an underside surface)that is opposite sliding surface 116. Evacuation slide 110 may comprisea forward edge 120 that is distal to engine 108 and an aft edge 122 thatis proximate to engine 108. Evacuation slide 110 may comprise aninflatable slide. FIG. 1 illustrates evacuation slide 110 in an inflatedand/or deployed position. Evacuation slide 110 may comprise a dual laneslide. However, evacuation slide 110 may comprise any number of lanes.Toe end 114 may be configured to contact an exit surface in response toevacuation slide 110 being deployed.

With reference to FIG. 2, evacuation slide 110 is illustrated in astowed and/or packed position. In this regard, evacuation slide 110 maybe stowed in a packboard 210. In various embodiments, evacuation slide110 may be folded in the stowed position. In various embodiments,evacuation slide 110 may be deployed from packboard 210 in response toopening an emergency exit door. Packboard 210 may be coupled to anaircraft in an installed position. Typically, a packboard 210 includes ablow-out panel which opens in response to deployment of evacuation slide110, and through which the inflatable slide may exit the packboard. Inthis regard, evacuation slide 110 may be configured to be deployed froman aircraft.

With reference to FIG. 3A and FIG. 3B, evacuation slide 110 isillustrated in a folded position, in accordance with variousembodiments. When evacuation slide 110 is in the folded or stowedposition, evacuation slide 110 may include a plurality of folds,including first fold 130 and second fold 132. A deployment assembly 128may aid in maintaining first fold 130 and second fold 132. Deploymentassembly 128 may also aid in a staged deployment of evacuation slide110. Deployment assembly 128 may include a releasable restraint 150.Releasable restraint 150 may aid in maintaining first fold 130 and/orsecond fold 132. Releasable restraint 150 may aid in a staged deploymentof evacuation slide 110. Evacuation slide 110 may unfold in response toreleasable restraint 150 separating.

In various embodiments, releasable restraint 150 may be configured toseparate in response to an internal pressure in evacuation slide 110.For example, a gas cylinder may supply a flow of pressurized fluid toevacuation slide 110 in response to evacuation slide 110 being deployed.Evacuation slide 110 may begin to inflate and an internal pressure ofevacuation slide 110 may increase. Releasable restraint 150 may maintainevacuation slide 110 in a folded position until the internal pressurehas increased above a predetermined threshold value. Releasablerestraint 150 may separate once the internal pressure of evacuationslide 110 has increased above the predetermined threshold value.Evacuation slide 110 may unfold in response to releasable restraint 150separating. In this regard, evacuation slide 110 may fully deploy inresponse to releasable restraint 150 separating.

In various embodiments, releasable restraint 150 may include a firstshackle 152 and a second shackle 154. Releasable restraint 150, firstshackle 152, and/or second shackle 154 may be metallic. In variousembodiments, releasable restraint 150 may comprise a shear pinrestraint. In this regard, a first portion 156 of releasable restraint150 may decouple from a second portion 158 of releasable restraint 150in response to a predetermined tensioning force illustrated by arrows160. A first cover 162 and/or a second cover 164 may surround releasablerestraint 150. Second cover 164 may surround at least a portion of firstcover 162. First cover 162 and second cover 164 may comprise a fabric.For example, first cover 162 and second cover 164 may comprise nylon,ballistic nylon, polypropylene, polyester, cotton, or other suitablematerial.

Deployment assembly 128 may include a head-end strap 170 coupled betweenevacuation slide 110 and releasable restraint 150. Head-end strap 170may be coupled to releasable restraint 150 via second shackle 154.Head-end strap 170 may be coupled to top surface 116 of evacuation slide110. An end 172 of head-end strap 170 may form a loop through whichsecond shackle 154 is located. In various embodiments, head-end strap170 may comprise a rope, tape, ribbon, webbing, or other suitable strap.In various embodiments, head-end strap 170 may comprise nylon, ballisticnylon, polypropylene, polyester, cotton, or other suitable material.

Deployment assembly 128 may include an asymmetric yoke 180 coupledbetween evacuation slide 110 and releasable restraint 150. Asymmetricyoke 180 may be coupled to releasable restraint 150 via first shackle152. Asymmetric yoke 180 may comprise a first strap 182, a second strap184, and restraint attachment portion 186. Restraint attachment portion186 may be located within first cover 162. First strap 182 and secondstrap 184 may be coupled to releasable restraint 150 via restraintattachment portion 186. In various embodiments, asymmetric yoke 180 maycomprise a rope, tape, ribbon, webbing, or other suitable strap. Invarious embodiments, asymmetric yoke 180 may comprise nylon, ballisticnylon, polypropylene, polyester, cotton, or other suitable material. Invarious embodiments, first strap 182, a second strap 184, and/orrestraint attachment portion 186 of asymmetric yoke 180 may comprise arope, tape, ribbon, webbing, or other suitable strap. In variousembodiments, first strap 182, a second strap 184, and/or restraintattachment portion 186 of asymmetric yoke 180 may comprise nylon,ballistic nylon, polypropylene, polyester, cotton, or other suitablematerial.

A yoke attach strap 181 may be coupled between asymmetric yoke 180 andevacuation slide 110. Yoke attach strap 181 may be coupled betweenasymmetric yoke 180 and underside surface 118 of evacuation slide 110.Yoke attach strap 181 may be coupled proximate to a center line ofevacuation slide 110, where the center line is parallel to alongitudinal axis of evacuation slide 110 extending from head end 112 totoe end 114 and is equal distance from forward edge 120 and aft edge 122of evacuation slide 110. In various embodiments, yoke attach strap 181may comprise a rope, tape, ribbon, webbing, or any other suitable strap.In various embodiments, yoke attach strap 181 may comprise nylon,ballistic nylon, polypropylene, polyester, cotton, or any other suitablematerial.

With reference to FIG. 3C, an end 188 of restraint attachment portion186 may form a loop 190 through which first shackle 152 is located.First strap 182, second strap 184, restraint attachment portion 186,yoke attach strap 181, and/or first cover 162 may be sewn together atbartack stitch 194. Restraint attachment portion 186 of asymmetric yoke180 may extend from first shackle 152 to bartack stitch 194. First strap182 of asymmetric yoke 180 may be coupled to a forward portion ofevacuation slide 110 proximate to forward edge 120 of evacuation slide110 (FIG. 1) such that first strap 182 extends from bartack stitch 194to the forward portion of evacuation slide 110. Second strap 184 ofasymmetric yoke 180 may be coupled to an aft portion of evacuation slide110 at aft edge 122 of evacuation slide 110 (FIG. 1), such that secondstrap 184 extends from bartack stitch 194 to the aft portion ofevacuation slide 110. In various embodiments, first strap 182 and secondstrap 184 may be sewn or otherwise attached to one another at box andcross stitch area 196 and then sewn as a single unit to restraintattachment portion 186 and/or first cover 162 at bartack stitch 194.Yoke attach strap 181 may be sewn or otherwise attached to first strap182, second strap 184, restraint attachment portion 186, and/or firstcover 162 at bartack stitch 194. Yoke attach strap 181 may extend frombartack stitch 194 to underside surface 118 of evacuation slide 110.

First strap 182 of asymmetric yoke 180 may be longer than second strap184 of asymmetric yoke 180. For example, with momentary reference toFIG. 6, a length L7 of first strap 182 extending from a first end 183 offirst strap 182 at bartack stitch 194 to a second end 185 of first strap182 that is opposite the first end 183 is greater than a length L8 ofsecond strap 184 extending from a first end 187 of second strap 184 atbartack stitch 194 to a second end 189 of second strap 184 that isopposite first end 187. The longer length of first strap 182, ascompared to second strap 184, allows forward edge 120 of evacuationslide 110 (FIG. 1) to open and/or inflate and/or unfold at a faster ratethan aft edge 122 of evacuation slide 110, prior to a separation ofreleasable restraint 150. Deployment assembly 128, including asymmetricyoke 180, may allow a forward portion of toe end 114 of evacuation slide110 to contact the exit surface prior to an aft portion of toe end 114.

With reference to FIGS. 4A, 4B, 4C, and 4D, staged deployment of anevacuation slide 110 from aircraft 100 is illustrated, in accordancewith various embodiments. With reference to FIG. 4A, a first stage of adeployment of evacuation slide 110 is illustrated, in accordance withvarious embodiments. An initial yoke 280 (also referred to as a head-endyoke) may be coupled to underside surface 118 of evacuation slide 110and the releasable restraint within first cover 162 and/or second cover164. Head-end strap 170 may be coupled to the releasable restraintwithin first cover 162/second cover 164 and to top surface 116 ofevacuation slide 110.

Head-end yoke 280 may include a first strap 282 and a second strap 284.First strap 282 may be coupled to first cover 162 (and/or the releasablerestraint within first cover 162) and to forward edge 120 of evacuationslide 110. Second strap 284 may be coupled to first cover 162 (and/orthe releasable restraint within first cover 262) and to aft edge 122 ofevacuation slide 110. In various embodiments, first strap 282 and secondstrap 284 of head-end yoke may be approximately the same length (i.e.,head-end yoke may be a symmetrical yoke). In other words, a length offirst strap 282 extending from a first end of first strap 282 at firstcover 162 to a second end of first strap 282 at forward edge 120 isapproximately equal to a length of second strap 284 extending from afirst end of second strap 284 at first cover 162 to a second end ofsecond strap 284 at aft edge 122. As used herein the phrase“approximately equal” means±5 inches (12.7 cm). In various embodiments,forward edge 120 and aft edge 122 may be equally inflated and/or openand/or unfolded, when the releasable restraint coupled between head-endyoke 280 and head-end strap 170 separates.

With reference to FIG. 4B, a second stage of a deployment of evacuationslide 110 is illustrated, in accordance with various embodiments. Afterseparation of the releasable restraint coupled between head-end yoke 280and head-end strap 170, first cover 162 and second cover 164 mayseparate such that first cover 162 goes with head-end yoke 280 attachedto underside surface 118 of evacuation slide 110 and second cover 164stays with head-end strap 170 on top surface 116 of evacuation slide110.

A first asymmetric yoke 380 may be coupled to underside surface 18 ofevacuation slide 110 and the releasable restraint within a first cover262 and/or a second cover 264. A head-end strap 270 may be coupledbetween top surface 116 of evacuation slide 110 and the releasablerestraint within first cover 262/second cover 264.

In various embodiments, first asymmetric yoke 380 includes a first strap382 and a second strap 384. First strap 382 may be coupled to firstcover 262 (and/or the releasable restraint within first cover 262) andto a forward portion of evacuation slide 110. Second strap 384 may becoupled to first cover 262 (and/or the releasable restraint within firstcover 262) and to an aft portion of evacuation slide 110. In variousembodiments, first strap 382 of first asymmetric yoke 380 is longer thansecond strap 384 of first asymmetric yoke 380. In other words, a lengthof first strap 382 extending from a first end of first strap 382 atfirst cover 262 to a second end of first strap 382 attached to theforward portion of evacuation slide 110 is greater than a length ofsecond strap 384 extending from a first end of second strap 384 at firstcover 262 to a second end of second strap 384 attached to the aftportion of evacuation slide 110. In various embodiments, first strap 382may be from 12 inches to 16 inches (30.4 cm to 40.6 cm) longer thansecond strap 384. In various embodiments, first strap 382 may be from 12inches to 28 inches (30.4 cm to 71.1 cm) longer than second strap 384.In various embodiments, first strap 382 may be from 12 inches to 45inches (30.4 cm to 114.3 cm) longer than second strap 384. In variousembodiments, first strap 382 may be from 6 inches to 9 feet (i.e., from15.2 cm to 274.3 cm) longer than second strap 384. In variousembodiments, a ratio of the length of first strap 382 to the length ofsecond strap 384 may be between 6:5 and 4:1.

The longer length of first strap 382, as compared to second strap 384,may allow forward edge 120 of evacuation slide 110 to inflate and/oropen and/or unfold a faster rate than aft edge 122 of evacuation slide110, prior to separation of the releasable restraint coupled betweenfirst asymmetric yoke 380 and head-end strap 270. Allowing forward edge120 to inflate and/or opening and/or unfold more than aft edge 122,prior to separation of the releasable restraint, may produce a flow ofwind across the top surface 116 of the evacuation slide 110 in a widthdirection, which is generally perpendicular to a longitudinal axis ofevacuation slide (i.e., an axis extending from head end 112 to toe end114). Allowing forward edge 120 to inflate and/or open and/or unfoldmore than aft edge 122, prior to separation of the releasable restraint,may produce downward force on the evacuation slide and create negativelift in windy conditions, thereby reducing the likelihood of “kiting” ofevacuation slide 110.

In various embodiments, the releasable restraint within first cover262/second cover 264 may be configured remain unseparated longer thanthe releasable restraint within first cover 162/second cover 164. Inother words, during deployment of evacuation slide 110, the releasablerestraint coupled to head-end yoke 280 may be configured to separateprior to the releasable restraint coupled to first asymmetric yoke 380.Configuring the releasable restraint coupled to first asymmetric yoke380 to separate after the releasable the releasable restraint coupled tohead-end yoke 280 may prevent kiting of evacuation slide 110 duringdeployment.

With reference to FIG. 4C, a third stage of a deployment of evacuationslide 110 is illustrated, in accordance with various embodiments. Afterseparation of the releasable restraint coupled between first asymmetricyoke 380 and head-end strap 270, first cover 262 and second cover 264may separate such that first cover 262 goes with first asymmetric yoke380 attached on the underside surface 118 of evacuation slide 110 andsecond cover 264 stays with head-end strap 270 on the top surface 116 ofevacuation slide 110.

In various embodiments, a second asymmetric yoke 480 may be coupled tounderside surface 118 of evacuation slide 110 and the releasablerestraint within a first cover 362 and/or a second cover 364. A head-endstrap 370 may be coupled to top surface 116 of evacuation slide 110 andthe releasable restraint within first cover 362/second cover 364.

Second asymmetric yoke 480 may include a first strap 482 and a secondstrap 484. First strap 482 may be coupled to first cover 362 (and/or thereleasable restraint within first cover 362) and to a forward portion ofevacuation slide 110. Second strap 484 may be coupled to first cover 362(and/or the releasable restraint within first cover 362) and to an aftportion of evacuation slide 110. In various embodiments, first strap 482of second asymmetric yoke 480 is longer than second strap 484 of secondasymmetric yoke 480. In other words, a length of first strap 482extending from a first end of first strap 482 at first cover 362 to asecond end of first strap 482 at the forward portion of evacuation slide110 is greater than a length of second strap 484 extending from a firstend of second strap 484 at first cover 362 to a second end of secondstrap 484 at the aft portion of evacuation slide 110. In variousembodiments, first strap 482 may be from 12 inches to 16 inches (i.e.,from 30.4 cm to 40.6 cm) longer than second strap 484. In variousembodiments, first strap 482 may be from 12 inches to 28 inches (30.4 cmto 71.1 cm) longer than second strap 484. In various embodiments, firststrap 482 may be from 12 inches to 45 inches (i.e., from 30.4 cm to114.3 cm) longer than second strap 484. In various embodiments, firststrap 482 may be from 6 inches to 9 feet (15.2 cm to 274.3 cm) longerthan second strap 484. In various embodiments, a ratio of the length offirst strap 482 to the length of second strap 484 may be between 6:5 and4:1.

The longer length of first strap 482 as compared to second strap 484 mayallow forward edge 120 of evacuation slide 110 to inflate and/or openand/or unfold at a faster rate than aft edge 122, prior to separation ofthe releasable restraint coupled between second asymmetric yoke 480 andhead-end strap 370. Allowing forward edge 120 to inflate and/or openand/or unfold more than aft edge 122, prior to separation of thereleasable restraint, may produce a flow of wind across the top surface116 of the evacuation slide 110 in a width direction, which is generallyperpendicular to the longitudinal axis of evacuation slide. Allowingforward edge 120 to inflate and/or open and/or unfold more than aft edge122, prior to separation of the releasable restraint, may producedownward force on the evacuation slide and create negative lift in windyconditions, thereby reducing the likelihood of “kiting” of evacuationslide 110.

In various embodiments, the releasable restraint within first cover362/second cover 364 may be configured remain unseparated longer thanthe releasable restraint within first cover 162/second cover 164 and/orlonger than the releasable restraint within first cover 262/second cover264. In other words, during deployment of evacuation slide 110, thereleasable restraint coupled to first asymmetric yoke 380 may beconfigured to separate after the releasable restraint coupled tohead-end yoke 280, and the releasable restraint coupled to secondasymmetric yoke 480 may be configured to separate after the releasablerestraint coupled to first asymmetric yoke 380.

In various embodiments, a difference in length between first strap 382and second strap 384 of first asymmetric yoke 380 may be greater than adifference in length between first strap 482 and second strap 484 ofsecond asymmetric yoke 480. In other words, a ratio of the length offirst strap 382 to second strap 384 may be greater than a ratio of thelength of first strap 482 to second strap 484.

With reference to FIG. 4D, a fully-deployed evacuation slide 110 isillustrated, in accordance with various embodiments. After separation ofthe releasable restraint coupled between second asymmetric yoke 480 andhead-end strap 370, first cover 362 and second cover 364 may separatesuch that first cover 362 goes with second asymmetric yoke 480 attachedon the underside surface 118 of evacuation slide 110 and second cover364 stays with head-end strap 370 on the top surface of evacuation slide110.

With reference to FIG. 5, a view of the underside surface 118 of anevacuation slide 110 in a deployed position is illustrated, inaccordance with various embodiments. In various embodiments, adeployment assembly 228 may be coupled to evacuation slide 110 andconfigured such that during deployment of evacuation slide 110 a forwardportion of toe end 114 contacts the exit surface prior to an aft portionof toe end 114. Deployment assembly 228 may comprise three yokes (e.g.,head-end yoke 280, first asymmetric yoke 380, and second asymmetric yoke480). Head-end yoke 280 may be located proximate to head end 112 ofevacuation slide 110 relative to first asymmetric yoke 380 and to secondasymmetric yoke 480. First asymmetric yoke 380 may be located proximateto head end 112 of evacuation slide 110 relative to second asymmetricyoke 480. Second asymmetric yoke 480 may be located proximate to toe end114 of evacuation slide 110 relative to first asymmetric yoke 380 and tohead-end yoke 280.

In various embodiments, head-end yoke 280 may be a symmetric yoke suchthat a length L1 of first strap 282 extending from a first end 283 offirst strap 282 located at cover 162 to a second end 285 of first strap282 coupled to a forward portion evacuation slide 110 proximate toforward edge 120 of evacuation slide 110 is approximately equal to alength L2 of second strap 284 extending from a first end 287 of secondstrap 284 located at first cover 162 to a second end 289 of second strap284 coupled to an aft portion of evacuation slide 110 proximate to aftedge 122 of evacuation slide 110. As used herein the term“approximately” means±5 inches (±12.7 cm). In various embodiments, L1may be between 24 inches and 90 inches (i.e., from 61.0 cm and 228.6 cm)and L2 may be between 24 inches and 90 inches (i.e., from 61.0 cm and228.6 cm). For example, L1 may be, approximately, 33 and ⅛ inches (84.1cm) and L2 may be, approximately, 33 and ⅛ inches (84.1 cm).

Yoke attach strap 181 may be coupled to first cover 162 and an area ofunderside surface 118 proximate to a center line 300 of evacuation slide110, where the center line 300 is parallel to a longitudinal axis ofevacuation slide 110 extending from head end 112 to toe end 114, and isequal distance from forward edge 120 and aft edge 122 of evacuationslide 110.

In various embodiments, first asymmetric yoke 380 of deployment assembly228 may be positioned closer to toe end 114 of evacuation slide 110 thanhead-end yoke 280. A yoke attach strap 281 may be coupled to first cover262 and an area of underside surface 118 proximate to center line 300 ofevacuation slide 110. A yoke attach strap 381 may be coupled to firstcover 362 and an area of underside surface 118 proximate to center line300 of evacuation slide 110.

First asymmetric yoke 380 may include first and second straps ofdifferent length. A length L3 of first strap 382 of first asymmetricyoke 380 extending from a first end 383 of first strap 382 located atfirst cover 262 to a second end 385 of first strap 382 coupled to aforward portion of evacuation slide 110 proximate to forward edge 120 ofevacuation slide 110 is greater than a length L4 of second strap 384extending from a first end 387 of second strap 384 located at firstcover 262 to a second end 389 of second strap 384 coupled to an aftportion of evacuation slide 110 proximate to aft edge 122 of evacuationslide 110.

In various embodiments, length L3 may be between 44 inches and 90 inches(i.e., from 111.8 cm and 228.6 cm) and length L4 may be between 24inches and 78 inches (i.e., from 61.0 cm and 198.1 cm). For example, L3may be, approximately, 49 and ⅛ inches (124.8 cm) and L4 may be,approximately, 33 and ⅛ inches (84.1 cm); L3 may be, approximately, 61and ⅛ inches (155.3 cm) and L4 may be, approximately, 33 and ⅛ inches(84.1 cm); L3 may be, approximately, 78 and ⅛ inches (198.4 cm) and L4may be, approximately, 33 and ⅛ inches (84.1 cm). As used herein theterm “approximately” means±5 inches (±12.7 cm).

In various embodiments, a ratio of length L3 to length L4 may be between6:5 and 4:1. For example, a ratio of length L3 to length L4 may be 3:2;a ratio of length L3 to length L4 may be 9:5; a ratio of length L3 tolength L4 may be 12:5.

In various embodiments, second asymmetric yoke 480 of deploymentassembly 228 may be positioned closer to toe end of 114 of evacuationslide 110 than head-end yoke 280 and first asymmetric yoke 380. A lengthL5 of first strap 482 of second asymmetric yoke 480 extending from afirst end 483 of first strap 482 located at first cover 362 to a secondend 485 of first strap 482 coupled to a forward portion of evacuationslide 110 proximate to forward edge 120 of evacuation slide 110 may begreater than a length L6 of second strap 484 extending from a first end487 of second strap 484 located at first cover 362 to a second end 489of second strap 484 coupled to an aft portion of evacuation slide 110proximate to aft edge 122 of evacuation slide 110.

In various embodiments, length L5 may be between 44 inches and 90 inches(i.e., from 111.8 cm and 228.6 cm) and length L6 may be between 24inches and 78 inches (i.e., from 61.0 cm and 198.1) cm). For example, L5may be, approximately, 49 and ⅛ inches (124.8 cm) and L6 may be,approximately, 33 and ⅛ inches (84.1 cm); L5 may be, approximately, 61and ⅛ inches (155.3 cm) and L6 may be, approximately, 33 and ⅛ inches(84.1 cm); L5 may be, approximately, 78 and ⅛ inches (198.4 cm) and L6may be, approximately, 33 and ⅛ inches (84.1 cm). As used herein theterm “approximately” means±5 inches (±12.7 cm).

In various embodiments, a ratio of length L5 to length L6 may be between6:5 and 4:1. For example, a ratio of length L5 to length L6 may be 3:2;a ratio of length L5 to length L6 may be 9:5; a ratio of length L5 tolength L6 may be 12:5.

In various embodiments, length L2, length L4, and/or length L6 may beapproximately equal. As used herein the phrase “approximately equal”means±5 inches (±12.7 cm).

In various embodiments, a difference between length L3 and length L4 isgreater than a difference between length L5 and length L6. For example,in various embodiments length L3 is from 28 inches to 50 inches longerthan length LA, and length L5 is from 12 inches to 28 inches longer thanlength L6.

In various embodiments, a ratio of length L3 to length L4 is greaterthan a ratio of length L5 to length L6. For example, in variousembodiments a ratio of length L3 to length L4 is from 9:5 to 4:1 and aratio of length L5 to length L6 is from 6:5 to 9:5.

Deployment assembly 228 may include any number of asymmetric and/orsymmetric yokes. In various embodiments, deployment assembly 228 mayinclude a plurality of asymmetric yokes. In various embodiments, adifference in length of the first straps of the asymmetric yokes to alength of the second straps of the asymmetric yoke may decrease in adirection of head end 112 to toe end 114 of evacuation slide 110 (i.e.,the difference in length of the first straps of the asymmetric yokes andthe second straps of the asymmetric yoke decreases the closer theasymmetric yoke is to toe end 114 of evacuation slide 110). For example,asymmetric yokes located closer to head end 112 of evacuation slide 110may have first and second straps with a greater difference in lengththan asymmetric yokes located closer to toe end 114 of evacuation slide110.

In various embodiments, a ratio of a length of the first straps of theasymmetric yokes to a length of the second straps of the asymmetricyokes may decrease in a direction of head end 112 to toe end 114 ofevacuation slide 110 (i.e., the ratio of the length of the first strapsof the asymmetric yokes to the length of the second straps of theasymmetric yoke decreases the closer the asymmetric yoke is to toe end114 of evacuation slide 110). For example, a ratio of a length of thefirst straps to a length of the second straps of asymmetric yokeslocated closer to head end 112 of evacuation slide 110 may be greaterthan a ratio of a length of the first straps to a length of the secondstraps of asymmetric yokes located closer to toe end 114 of evacuationslide 110.

In various embodiments, a decrease in a difference in a length of thefirst straps of the asymmetric yokes to a length of the second straps ofthe asymmetric yoke is related to a timing of the separation of thereleasable restraints coupled to the asymmetric yokes. For example,asymmetric yokes coupled to releasable restraints that separate earlierin the deployment of evacuation slide 110 may have first and secondstraps with a greater difference in length than asymmetric yokes coupledto releasable restraints that separate later in the deployment ofevacuation slide 10.

With reference to FIG. 7, a method 400 of making an evacuation assemblyis provided, in accordance with various embodiments. The method 400comprises coupling a first yoke comprising a first strap longer than asecond strap to an evacuation slide (step 402). Method 400 may includecoupling the first strap to a forward portion of the evacuation slideand coupling the second strap to an aft portion of the evacuation slide(step 404). Method 400 may include coupling a second yoke comprising afirst strap longer than a second strap to the evacuation slide (step406). Method 400 may include coupling the second yoke closer to a toeend of the evacuation slide than the first yoke (step 408).

In various embodiments, with combined reference to FIG. 5 and FIG. 7,step 402 may include coupling first asymmetric yoke 380 comprising firststrap 382 longer than second strap 384 to evacuation slide 110. Step 404may include coupling first strap 382 to a forward portion of evacuationslide 110 and coupling second strap 384 to an aft portion of evacuationslide 110. Step 406 may include coupling second asymmetric yoke 480comprising first strap 482 longer than second asymmetric yoke 480 toevacuation slide 110. Step 408 may include coupling second asymmetricyoke 480 closer to toe end 114 of evacuation slide 110 than firstasymmetric yoke 380.

Benefits, other advantages, and solutions to problems have beendescribed herein with regard to specific embodiments. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent exemplary functional relationships and/or physicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships or physicalconnections may be present in a practical system. However, the benefits,advantages, solutions to problems, and any elements that may cause anybenefit, advantage, or solution to occur or become more pronounced arenot to be construed as critical, required, or essential features orelements of the disclosure.

The scope of the disclosure is accordingly to be limited by nothingother than the appended claims, in which reference to an element in thesingular is not intended to mean “one and only one” unless explicitly sostated, but rather “one or more.” It is to be understood that unlessspecifically stated otherwise, references to “a,” “an,” and/or “the” mayinclude one or more than one and that reference to an item in thesingular may also include the item in the plural. All ranges and ratiolimits disclosed herein may be combined.

Moreover, where a phrase similar to “at least one of A, B, and C” isused in the claims, it is intended that the phrase be interpreted tomean that A alone may be present in an embodiment, B alone may bepresent in an embodiment, C alone may be present in an embodiment, orthat any combination of the elements A, B and C may be present in asingle embodiment; for example, A and B, A and C, B and C, or A and Band C. Different cross-hatching is used throughout the figures to denotedifferent parts but not necessarily to denote the same or differentmaterials.

The steps recited in any of the method or process descriptions may beexecuted in any order and are not necessarily limited to the orderpresented. Furthermore, any reference to singular includes pluralembodiments, and any reference to more than one component or step mayinclude a singular embodiment or step. Elements and steps in the figuresare illustrated for simplicity and clarity and have not necessarily beenrendered according to any particular sequence. For example, steps thatmay be performed concurrently or in different order are illustrated inthe figures to help to improve understanding of embodiments of thepresent disclosure.

Any reference to attached, fixed, connected or the like may includepermanent, removable, temporary, partial, full and/or any other possibleattachment option. Additionally, any reference to without contact (orsimilar phrases) may also include reduced contact or minimal contact.Surface shading lines may be used throughout the figures to denotedifferent parts or areas but not necessarily to denote the same ordifferent materials. In some cases, reference coordinates may bespecific to each figure.

Systems, methods and apparatus are provided herein. In the detaileddescription herein, references to “one embodiment”, “an embodiment”,“various embodiments”, etc., indicate that the embodiment described mayinclude a particular feature, structure, or characteristic, but everyembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to affect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed. After reading the description, it will be apparent to oneskilled in the relevant art(s) how to implement the disclosure inalternative embodiments.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element is intended to invoke 35 U.S.C. 112(f)unless the element is expressly recited using the phrase “means for.” Asused herein, the terms “comprises”, “comprising”, or any other variationthereof, are intended to cover a non-exclusive inclusion, such that aprocess, method, article, or apparatus that comprises a list of elementsdoes not include only those elements but may include other elements notexpressly listed or inherent to such process, method, article, orapparatus.

What is claimed is:
 1. An evacuation assembly, comprising: an evacuationslide; and a deployment assembly coupled to the evacuation slide andconfigured such that during a deployment of the evacuation slide aforward portion of a toe end of the evacuation slide contacts an exitsurface prior to an aft portion of the toe end of the evacuation slide.2. The evacuation assembly of claim 1, wherein the deployment assemblycomprises a first yoke comprising a first strap and a second strap,wherein the first strap is longer than the second strap.
 3. Theevacuation assembly of claim 2, wherein the first strap is coupled to aforward portion of the evacuation slide and the second strap is coupledto an aft portion of the evacuation slide.
 4. The evacuation assembly ofclaim 2, wherein a ratio of a length of the first strap to a length ofthe second strap is from 6:5 to 4:1.
 5. The evacuation assembly of claim2, wherein the first strap is between 6 inches and 9 feet longer thanthe second strap.
 6. The evacuation assembly of claim 2, wherein thedeployment assembly further comprises a second yoke, wherein a firststrap of the second yoke is longer than a second strap of the secondyoke.
 7. The evacuation assembly of claim 6, wherein the second yoke islocated closer to the toe end of the evacuation slide than the firstyoke.
 8. The evacuation assembly of claim 7, further comprising: a firstreleasable restraint coupled between the first yoke and the evacuationslide; and a second releasable restraint coupled between the second yokeand the evacuation slide, wherein the first releasable restraint isconfigured to separate prior to the second releasable restraint duringthe deployment of the evacuation slide.
 9. The evacuation assembly ofclaim 3, wherein a difference in a length of the first strap of thefirst yoke and a length of the second strap of the first yoke is greaterthan a difference in a length of the first strap of the second yoke anda length of the second strap of the second yoke.
 10. The evacuationassembly of claim 3, wherein the deployment assembly further comprises athird yoke coupled to the evacuation slide, wherein a first strap of thethird yoke and a second strap of the third yoke are approximately equalin length.
 11. The evacuation assembly of claim 10, wherein the thirdyoke is positioned closer to a head end of the evacuation slide than thefirst yoke and the second yoke.
 12. A yoke for an evacuation system,comprising: a first strap; and a second strap coupled to the firststrap, wherein the first strap is longer than the second strap.
 13. Theyoke of claim 12, wherein a ratio of a length of the first strap to alength of the second strap is from 6:5 to 4:1.
 14. The yoke of claim 12,wherein the first strap is from 6 inches to 9 feet longer than thesecond strap.
 15. The yoke of claim 12, wherein the first strap andsecond strap are sewn together.
 16. A method of making an evacuationassembly, comprising: coupling a first yoke to an evacuation slide, thefirst yoke comprising, a first strap, and a second strap, wherein thefirst strap is longer than the second strap; coupling the first strap toa forward portion of the evacuation slide; and coupling the second strapto an aft portion of the evacuation slide.
 17. The method of claim 16,wherein a ratio of a length of the first strap to a length of the secondstrap is from 6:5 to 4:1.
 18. The method of claim 16, further comprisingcoupling a second yoke to the evacuation slide, wherein a first strap ofthe second yoke is longer than a second strap of the second yoke. 19.The method of claim 18, wherein a difference in a length of the firststrap of the first yoke and a length of the second strap of the firstyoke is greater than a difference in a length of the first strap of thesecond yoke and a length of the second strap of the second yoke.
 20. Themethod of claim 19, further comprising coupling the second yoke closerto a toe end of the evacuation slide than the first yoke.